Hydrosulfite compound and process of making same.



cerea entrant stains Parana. mes.

ANTON WEINDEL, or MuLH iM N-T'HE RHINniGERMANY, ASSIGNOR TO FARBEN-FABRIKEN VORM. FRIEDR. BAYEnaco or ELBERFELD, GERMANY, acoarom TION F(Bi-EJRJlIIANY.

HYDROSULFITE' COMPOUND Arm moonss or MAKING SAME.

No Drawing.

' To aZZ'whom it may concern:

quantity calculated according to the equation a zinc hydrosulfite isobtained which is difficultly soluble in water.- Investigation howeverhas shown that no zinc hydrosulfite is produced by this process but adouble salt' consisting of varying amounts of zinc, .sodium, sulfurousand hydrosulfurous acid.

I have made the surprising discovery that contrary to the presentknowledge according to which excess of acid must be absolutely avoidedwith zinc hydrosulfite, an exceedingly stable double salt, 2ZnS O Na SOcontaining a very high percentage of zinc hydrosulfite (75.5per cent.)is obtained if solid or dissolve-d bisulfites are added to a solution ofzinc hydrosulfit'e; the present invention' relates to the manufactureand production of this new salt In order vto illustrate the new processmore fully the following example is given, the parts being by weight. ITo 100 parts of a solution of zinc hydrosulfite containing 32.5 percent. Z11S,(),,'92 parts of a solution of sodium bisulfiteof 37 B. areadded. The mixture thus obtained is then stirred for some time while itis gently heated to about 55 C. The above mentioned double compoundwhich separates out during the heating is thus obtained in the shape ofgranular crystals.

The formation of my new compound prob- Application filed December 21,1909. Serial No. 534,350.

Specification b: LettersPateilt. I Patented J une ts-1910 ably takesplace according to the-following formula of it are solublein 100 partsof. water at the ordinary temperature. It is insoluble in I organicsolvents such asalcohol, ether and benzene, soluble 'in caustic soda,lye; the sodium salt of hydrosulfurous acid being formed, while thezinc is precipitated as Zn(OH) 2 being dissolved again by an excess ofalkali as zincate. l'grarnof sulfur contained in the double salt reducesabout: 3,291 grams ofindigotin.

My new compound may be employed as an agent of reduction and also as astarting material for the manufacture of sodium hy- The bisulfiteemployed in the above process can alsobe' used in a solid-state.

I claim-.-

1. The herein described process for producing a new solid and stablezinc hydrosulfite sodium sulfite (QZnS O NafiOQ, which process consistsin treating mixing together and crystallizing solutions .of' zinchydrosulfite with alkali. bisulfite, substantially as described. i

2. The herein described zinc hydrosulfite sodium sulfite of the formula:

witnesses;

ANTON IVEINDEL. [1,. s.] 'Witness's Orro .Koivic, CHAS. J. WRIGHT.

